The Locus of Centres Method for LDA and PDA Measurements
A new method is introduced for the analysis of LDA and PDA optical setups, especially suited for larger particles or bubbles. The properties of an optical setup are studied for a specific particle size in an effective control volume defined as the Locus of the Centres of the particles producing interference signals. The effect of the particle size on the size and position of such a control volume are evaluated and discussed. The convenient description using control volume fringes is adapted to suit larger particles and used to derive the equations of LDA and PDA measurements. The method sets new standards for the estimation of the active control volume as a function of the particle size, for dispersed two phase flows measurements.
KeywordsLocus of Centres method LDA PDA
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